Ignition means for oil burners



June 11, 1940.

R. D. SCHOEN WETTER IGNITION umus FOR OIL URNEfRs Filed Oct. s, 1936 3 Q'etS-Sheet i June 11, 1940.

R. D. SCHQENWETTER IGNITION MEANS FOR OIL BURNERS I Filed Oct. 5. 1936 3 eet "a dumm R1 D. SJCHOENWETTER 2,204,450 mum; mums FOR 011; mmurms June 11, 1940.

s Sheefs-Sheet 3 Filed 091:. 5, 193a Patented June 11, 1940 I UNITED STATES PATENT OFFICE IGNITION MEANS FOR on. BURNERS Reinhold n. Schoenwetter, can a va, u-

slgnor' to Swirling Heat,

Delaware Inc., a corporation of Application embel- 5, 1936', swarm. 104,068 14 cu s. (01.15pm

This invention relates to oil burners of the type generally employed for purpose of heating household furnaces and particularly to ignition means for such a burner.

The majority of the oil burners now sold on the market depend almost entirely upon electrical means for their ignition and in many instances the so-called electric spark system is used. In order to employ the-electric spark ignition system, it is necessary to provide electrodes mounted in the proximity of the burner head in .such 7 a position that the sparking ends thereof; are in the best zone of ignition. Due to the use of arious designs of deflector plates for directing the flow of air which intermingles with the atomized fuel to support combustion, the zone .of best ignition hasbecome critical and necessitates such a fineness of positioningof the electrodes that numerous adjustmentsare necessary before proper setting is obtained. As far as I am aware, no means have heretofore been devised whereby one could effect this adjustment from a point outside of the furnace., The customary methods utilized heretofore have been, for ex-' ample, the grasping of the electrodes and bending them to properly position them relative ,to the zone of best ignition which for obvious reasons is impracticable since it is very dimcult' to see whether or not the proper spacing of the elec-,

trodes to give the best igniting spark has been retained while making the adjustment; Attempts have been made to overcome thisdifliculty by providing mirrors within the furnace so disposed that the operator can by looking in the furnace door inspect the relative positions of the electrodes. I

Therefore an object-oi thisinvention isthe provision of means whereby, without altering the relative adjustment of the electrodes, the elec trodes maybe positioned in the zoneof best ignition from a point outside the furnace. r

This invention further contemplates the provision of an electrode assembly suchqthat the electrodes and their mountmay bereadilydetached as a unit for inspection and relative ad- I justment without the necessity of loosening. any

screws or bolts. I I,

This invention further contemplates the provision of an electrode assembly suchthat the electrodes and their mount may be readily detachedlas a unit for inspection and relative adjustment andwhen replaced will be'in the same relative position tothe [zone ofcombustion.

Other features and advantages will appear Figure 6;

position of the ignition currentconductors there- Figure 4 is a fragmentary vertical section of an oil burner showing in detail the adjusting means for the ignition electrodes;

Figure'5 is a fragmentary cross-sectional view taken along the line 55 of Figure 4 showing the ignition current transformer mounted on the burnercasing; a

"Figure 6 is a fragmentary sectional view of a burner headshowingthe ignition electrode assembly in detailed elevation;

' Figure 7 is a side view of 'a burner head showing theelectrode assembly mounted thereon;

Figure 8 is a horizontal section of the burner 4. assembly ,taken along the line 8-8 of Figure 6 showing the adjusting cam;

- I Figure '9 is a horizontal sectional view of the electrode assembly taken along the line 9-9 of ,Figure 10 is a perspective view of the inner section oi the insulating r-electrode mount; and

Figure his a perspective-view of the outer section of the insulating electrode mount.

Referring to the drawings in detail, particularly Figure 1, an oil-burner indicated generally as it! having a primemover H, a fan II, a fuel pump [3, an air blast tube l4,and a burner head I5, is shown, operatively assembled on a supporting lframe 16 made integrally with the fan casing I'l transformer 18, the primary circuit of which is adapted to be supplied with an electric current from a source, not shown, is secured to the, frame by bolts [9, and formsa closure for an opening 20, at a point directly under the lprimejmoverrllu Leads 2| from the secondary winding of the transformer l8 arebroughtout of thetransformer'case and project through insulating' bushings 22 into the bottom portion of .the fan casing H which forms an'air passage fromtheffa'n l2 and communicates'at its outer end withthe ,air blast tube II. I Air blast tube' I4 is longitudinally'divided by a vertical partition 2-3, preferably of sheet metal, into two independentpassages 24 and 25. Disposed within the passage 24 are electrical conductors 23 which connect by means of connectors 21 the leads 2| from the secondary winding of the transformer to connectors 3 carried by the inner insulating block 23 of the electrode assembly. Passage 25, having disposedtherein the oil supply conduit 33, serves to connect the fancasing to the burner head. Partition 23 accordingly prevents any possibility of injury to conductors 23 by the in sertion or removal of conduit 33. An electrode adjusting rod 3| having an operating knob 32 suitably secured to the outer end thereof, passes through the openings 33 and34 in the frame l5 and the fan casing II, respectively, and extends through the passage 24 and the opening 35 in the burner head casing 33 and is secured against endwise movement by locking nuts 31.- Sufficient clearance is left between the nuts 31 and the casing wall 33 of the burner head to permit the rod 3| to turn freely in the opening. 35. The inner end of the adjusting rod 3| is threaded back sufllciently far from the end thereof to permit the electrode assembly adjusting cam 33 which threadedly engages the adjusting rod 3| to move along the rod a distance at least equal to its own length. Cam 33, as shown in detail in Figures 4, 6 and 8 has formed on its opposite ends lugs 33 and 43. Lug 33 is provided with an opening 4| of suflicient diameter-that it will slide freely on the adjusting rod 3| while lug 43 is provided with openings 42 and 43. Opening 42 is tapped to receive the threaded adjusting rod 3| and the opening 43 is of sufficient diameter to permit .the guide rod 44 to slide freely therein. Guide rod 44, which cooperates with the lug- 43 to prevent the cam 33 from being rotated by the adjusting rod 3|, is rigidly secured to and projects from the burner head casing 33.

Cam 33 is adapted to slide on and actuate a shoulder 45 that is made integrally with the inner v insulating block 23. Insulating block 23 extends through an opening 43 in the burner head casing 33 and by means of pivot pin 41' is pivotally -in the plate 43 and block 23, respectively, and

exert a force on the upper half of block 23 which tendsv to cause the top of the block to pivot outwardly to its extreme position.

Conductor connectors 23 are secured by screws 53 within recesses 54 formed in the inner face of the insulating block 23. Screws 53 besides being current conductors also serve as securing means for the male section 55 of a set of snap-on connectors that are disposed in recesses 53 in the opposite face of block 23, as shown in Figures 9 and 10. A peripheral flange 51 made integrally with block 23 extends outwardly from the outer face thereof to form a recess for a second insulating block 53. Block 53 is substantially rectangular in shape and has transverse passages 53 formed in the longitudinal edgw thereof adapted to receive bosses 33 formed on the inner face of the flange 51. Bosses 33 in addition to providing suflicient material to define the recesses 5| serve as means for aligning the two blocks when assembled in operative relationship and are disposed in such a manner that the blocks can only be assembled in one way.

As shown in detail in Figure 9, the female end 3| of snap-on connectors are secured by suitable bolts 32 to the block 53 in recesses 33 formed in the inner face of the block. These connectors are in alignment with and adapted to be secured by snap-on engagement to the male sections 55 secured to the outer face of block 23. Block 53, as shown in Figures 9 and 11,, is provided with openings 34 that are counterbored from their inner face to receive bolts 35 by which the respective electrode brackets 33 and 31 are secured in parallel spaced relationship to the outer face of block 53. The brackets are identical and may be used interchangeably. That arm of each bracket which projects laterally from the face of block 53 is drilled to provide a substantially vertical passagewayfor electrodes 53. The electrodes 33 are secured in the passageways by means of set screws 33. Each of the brackets is horizontally mounted but with their ends which carry the electrodes oppositely disposed so that when the electrodes are secured in the brackets in operative position, they are spaced and substantially parallel. The enlarged body portion of the electrodes 33 may be formed of any suitable electric current conducting material, such as iron, steel, copper, brass, etc. While that portion of the electrodes of reduced diameter, preferably formed of an alloy of nickel and chromium commonly known by the trade-name nichrome", is subjected to the heat of the burner flame and is in the form of wire which is bent so that the ends 1| thereof project over the burner head into the zone of ignition. The spacing of the points ll of these electrodes is dependent upon the voltage supplied by the secondary of the transformer I3 and the intensity of the igniting spark desired. The nichrome wires 13 aresecured to the body supports in any suitable manner such as by threaded engagement, shrinking or sweating.

In operation to effect a positioning of the points ll of the electrodes with respect to the ignition zone from a point outside the furnace, one grasps the operating knob 32 and rotates the rod 3| in a direction dependent upon the direction in which it is desired to move the points of the electrodes that is, into or out of the combustion area. Rotation of rod 3| causes the cam 33, which is in threaded engagement therewith, to move along the shoulder 45 and cause block 23, which carries the electrode assembly, to be pivoted about its axis formed by the pin 41'. Cam 33 when moved toward the inner end of the operating rod 3| forces the top of the block 23 inwardly against the action of the coil springs 43. and on movement of the cam 33 in the opposite direction, these springs 43 tend to pivot the top of block 23 outwardly and thereby keep the shoulder 45 in contact with the cam 33 at all times. In this manner one is enabled to adjustably position the points 1| of the electrodes relative to the point of best ignition by means extending outside of the furnace. Insulating block 53 that carries the electrodes 33 being connected in operative position to block 23 by snap-on connectors may be readily detached without the necessity of loosening any screws or bolts to conveniently adjust the spacing of the points II of the electrodes.

I claim:

1. In an oil burner the combination of a burner head having an upper opening and a side opening, means for supplying fuel to said head, means for igniting said fuel, means for supporting said igniting means in a position adjacent said upper opening, said supporting means being movable and positioned in said side opening, and means for adjusting the position of said ignitingmeans with respect to said upper opening, said means extending from a point inside said burner head adjacent said supportingmeans to a point outside the oil burner.

2. In an oil burner the combination of a burne head having an upper opening and a side opening, means for supplying fuel and air to saidhead, means for igniting said fuel and air as it emerges from said upper opening, insulated means for supporting said igniting means in a position adjacent said upper opening, said supporting means being movable and positioned in said side opening, and means for adjusting the position ofsaid igniting means with respect to said upper opening,

said means being contiguous with said insulated supporting means and extending from a point inside said burner head to a point entirely outside the burner.

3. In an oil burner the combination of a burner head having an upper opening and a side opening, an atomizing nozzle disposed within the burner head below said upper opening, means for supplying fuel to said nozzle, means for supplying air to said head, means for igniting the mixture of fuel and air emerging from said upper opening, insulated means for supporting said igniting means in a position adjacent said upper opening, said supporting means being pivotally positioned in said side opening for movement about an horizontal axis, and means for adjusting the position of said igniting means with respect to said upper opening, said means being contiguous with said supporting means and extending from apoint inside said head adjacent said supporting means to a point completely outside the oil burner.

4. In an oil burner the combination of a burner head having an upper opening and a side opening, a vertically disposed atomizing nozzle within said head below said upper opening, bafile means surrounding said nozzle, means for: supplying fuel under'pressure to said nozzle, means for supplying air under pressure to said baflie means, said air supply means comprising an air blast tube and an encased fan, means for igniting the mixture of fuel and air escaping through said upper opening, insulated means for supporting said igniting means in a position adjacent said upper opening, said supporting means being positioned in said side opening and being pivotally mounted for movement about an horizontalaxis, and means for adjusting the position of said igniting means with respect to said upper opening,

said means comprising a manually rotatable rod and a cam member capable of reciprocating movement along said rod only, said cam member being contiguous with said supporting means and said rod extending from a point inside said head adjacent said supporting means through said air blast tube and the casing of said fan to a point completely outside the oil burner.

5. In an oil burner the combination of a burner head having an upper opening, a vertically disposed atomizing nozzle within said head below said opening, baflle means surrounding said nozzle,

means for supplying fuel to said nozzle, means for supplying'airto said,baflle means, means for igniting the "mixture-of fuel and air escaping from said opening; eans for supporting said igniting for moving said supporting-means from a remote point", wherebysaid igniting means is moved to.-

of said head for movement toward and away from said headand being normally spring-pressed away from said head, andmeans positioned on the inside of said head andextending to ED801112- side of said oil burner for adjustably moving said ignition means toward said head.

7. In an oil burner the combination of a burner head, an ignition means therefor, said ignition means comprising a supporting member and a plurality of vertically extending ignition rods having substantially horizontal portions at their upper ends extending toward said head, said supporting member being pivotally mounted in the side wall of said head and said rodsbeing movable in an arcuate' path toward and away from said head and being normally yieldably held relatively away from said head, and means positioned on the inside of said head adjacent said supporting member for adjustably moving said ignition rods relatively nearer said head.

8. In an oil burner, the combination of a burner head ignition means for'said burnerpositioned on the outside of said headand movable toward and away from said head, and means inside said head and extending outside said burner for actuating said ignition means, said ignition means being. mounted on an insulated member pivotally positioned in the side wall of said head and having a cam surface thereon, and said actuating means comprising a rotatable rod and a cam member longitudinally movable along said rod and cooperating with said cam surface to move rod extending from a point inside said head to a point outside said burner, a cam member positioned on said rod and threaded thereto for longitudinal movement therealong as said rod is rotated, and means for preventing said cam member from rotating, said cam member contacting a portion of said ignition means, whereby said ignition means is moved as said cam member is moved along said, rod.

10. In an oil burner the combination of a burner head, means for supplying fuel to said head, means for supplying air to said head comprising an encased'fan and an air blast tube extending from said fan casing to. said head, ignition means for igniting the mixture of fuel and air supplied to said head, said ignition means-being movably mounted in a side wall of said head, and means for moving said ignition means extending from a point inside said head adjacent said ignition means through said air blast tube and the casing of said fan to a point outside the'burner.

11. In an oil burner the combination of a burner head, an ignition means, and means for supporting said ignition means in a position adjacent said head, said ignition means comprising a pair of vertically extending electrodes which are rotatable about their own vertical axes and have inclined upper end portions, and said supporting means being removably mounted in the side wall of said head, whereby said electrodes may be removed as a unit and rotated about said axes to vary the distance between said end portions.

12. 111 an oil burner the combination of a burner head, an ignition means, and means for supporting said ignition means in aposition adjacent said head, said ignition means comprising a pair of vertically extending electrodes which are rotatable about their own vertical axes and have inclined upper end portions, whereby said electrodes may be rotated about said axes to vary the distance between said end portions, and said supporting means being fastened to the side wall of said head by a snap-on means in a predetermined position in said wall, whereby said supporting and ignition means may be readily detached and reattached in exactly their original position with respect to said wall.

13. In an oil burner the combination of a burner head, an ignition means therefor, and means for moving said ignition means from a point outside the burner, said ignition means comprising a plurality of vertically extending rods which are rotatable about their own vertical axes and have inclined ignition points at their upper ends and being mounted on an insulated member having a plurality of separable portions, one portion supporting said igniting means and another portion being pivotally mounted on the side of said head, whereby said ignition rods may be jointly moved toward and away from said burner head from a point outside said burner and may be removed entirely from said burner to adjust the distance of said points from each other.

14. In an oil burner, the combination of a burner head and an ignition means therefor, means for supporting said ignition means, means for moving said supporting means and said ignition means from a point outside the burner, said.

ignition means comprising a pair of rods extending from said support into the zone of ig- 

